Component bindings in Svelte - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a component binding in Svelte?

A component binding in Svelte connects a variable in a parent component to a property or value inside a child component, allowing two-way data flow.

beginner

How do you bind a variable to an input element in Svelte?

Use the bind:value directive on the input element, like <input bind:value={name} />, to keep the variable name and the input's value in sync.

intermediate

What happens when you use bind:this in Svelte?

The bind:this directive assigns a reference of the DOM element or component instance to a variable, letting you interact with it directly in your script.

intermediate

Can you bind to custom component props in Svelte? How?

Yes, by using bind:propName on the child component tag, you can create two-way binding between the parent variable and the child's prop.

beginner

Why is two-way binding useful in Svelte components?

Two-way binding keeps data synchronized between parent and child components automatically, reducing the need for manual event handling and making UI updates simpler.

Which directive is used to bind a variable to an input's value in Svelte?

A bind:model

B bind:input

C bind:data

D bind:value

The correct directive is bind:value to connect a variable to an input's value.

What does bind:this do in a Svelte component?

A Binds a variable to the DOM element or component instance

B Binds a variable to the component's CSS class

C Binds a variable to the component's event

D Binds a variable to the component's style

bind:this assigns a reference of the DOM element or component instance to a variable.

How do you create two-way binding with a custom prop in a child component?

A Use bind:custom on the child component tag

B Use bind:propName on the child component tag

C Use bind:this on the child component tag

D Use bind:value on the child component tag

Two-way binding with custom props uses bind:propName on the child component.

What is a benefit of using component bindings in Svelte?

A It disables user input

B It makes the code run faster

C It automatically synchronizes data between components

D It removes the need for CSS

Component bindings keep data synchronized automatically between components.

Which of these is NOT a valid use of binding in Svelte?

A bind:style on a component

B bind:this on a DOM element

C bind:value on an input element

D bind:propName on a child component

bind:style is not a valid binding directive in Svelte.

Explain how two-way binding works in Svelte components and give an example with an input element.

Think about how typing in an input updates a variable and vice versa.

Describe the purpose of bind:this in Svelte and when you might use it.

Consider when you need to call a method or focus an element directly.